Nuclear medical diagnostic apparatus and method for detecting radiation

Abstract

A method for detecting radiation emitted from a radiation source within a subject. A radiation detector is moved in approximately parallel with the direction of the body axis of the subject. The detector is rotated about the body axis. The distance between the subject and the detector is changed. The radiation is detected by the detector.

1 . A nuclear medical diagnostic apparatus for detecting radiation emitted from a radiation source within a subject, comprising: 
 a base which is moveable in a linear direction;    a circular ring configured to move along with the base;    a first gear provided inside the circular ring;    a second gear engaged with the first gear to move in the circumferential direction of the ring;    a first moving component rotatable about a first axis and configured to move along with the second gear in the circumferential direction of the ring;    a second moving component cooperating with the first moving component;    a table coupled to the second moving component and moveable in a direction parallel with the first axis when the first moving component is rotated; and    a first detector to detect the radiation, the detector configured to move along with the table.    
   
   
       2 . A nuclear medical diagnostic apparatus according to  claim 1 , wherein the first gear comprises a sun gear, the second gear comprises a planet gear, the first moving component comprises a ball screw, and the second moving component comprises an internal thread receiving the ball screw to move along the axis of the ball screw.  
   
   
       3 . A nuclear medical diagnostic apparatus according to  claim 2 , comprising: 
 a guide rail coupled to the circular ring;    a bearing supporting the second gear to permit movement of the second gear along the guide rail in the circumferential direction of the ring.    
   
   
       4 . A nuclear medical diagnostic apparatus according to  claim 2 , wherein the ball screw is arranged to substantially form a tangent line to the circular ring.  
   
   
       5 . A nuclear medical diagnostic apparatus according to  claim 2 , wherein the detector is rotatable on its axis.  
   
   
       6 . A nuclear medical diagnostic apparatus according to  claim 5 , wherein the axis of the rotation of the detector is orthogonal to both the direction of the axis of the ball screw and the linear direction.  
   
   
       7 . A nuclear medical diagnostic apparatus according to  claim 2 , wherein the detector is provided with a two-dimensional array of semiconductor detectors to detect the radiation.  
   
   
       8 . A nuclear medical diagnostic apparatus according to  claim 7 , wherein the table cantilevers the detector.  
   
   
       9 . A nuclear medical diagnostic apparatus according to  claim 2 , wherein the radiation is gamma radiation.  
   
   
       10 . A nuclear medical diagnostic apparatus according to  claim 2 , comprising a second detector to detect the radiation.  
   
   
       11 .- 19 . (canceled)